1. Field of the Invention
This invention relates to communication systems, more particularly the present invention relates to an approach supporting over-the-air (xe2x80x9cOTAxe2x80x9d) service programming of a mobile station.
2. Description of the Related Art
Conventionally, an activation process for a newly purchased mobile station is a manually intensive and time consuming process. One of the limitation with this conventional activation process is that the user must bring the mobile station to a service center in order to activate the mobile station.
A Mobile Station is a subscriber station in the category of Domestic Public Cellular Radio Telecommunications Service, normally intended to be used while in motion or during halts at unspecified points. The category includes true mobile stations, handheld portable stations, fixed stations, and other devices.
At the service center a technician programs (stores) into the mobile station various parameters which include information that allows the unit to communicate on the network and which define the mobile station""s network identity. Optionally, manufacturer specific information may also be programmed into the mobile station. Multiple parameter sets are sometimes provided in a mobile station so that, for example, the mobile station can have local identities in different service areas.
If information stored in a previously activated mobile station needs to be changed, conventionally the process is also manually intensive and time consuming. One of the limitations with this conventional process is that the user must bring the mobile station to a service center in order to have a technician change the information in the mobile station.
Accordingly, one object of this invention is to provide a novel method to activate a mobile station for use within a communications network without the user having to bring the mobile station to a service center or third party.
Another object of this invention is to provide a novel method to change information in a mobile station for use within a communications network without the user having to bring the mobile station to a service center or third party.
Hereafter, these two objects of this invention, namely to activate a mobile station and to change information within a mobile station without the user having to bring the mobile station to a service center or third party will be referred to as over-the-air service programming (OTASP).
Another object of the present invention is to provide a signaling infrastructure to accomplish the over-the-air service programming of a mobile station for use within a communications network with minimal mobile switching center (MSC) and visitor location register (VLR) involvement.
The above and other objects are achieved according to the present invention by providing a new and improved signaling infrastructure and method for over-the-air service programming of a mobile station for use in a communications network.
According to the invention, the mobile station transmits a message including an over-the-air service programming request, the mobile station identification presently stored in the mobile station and the mobile station""s electronic serial number, to a mobile switching center coupled to the communications network. If the mobile station can have multiple identities, as discussed above, the user selects the mobile station identity to be in effect during the over-the-air service programming procedure.
An Electronic Serial Number is a 32-bit number assigned by the mobile station manufacturer, uniquely identifying the mobile station equipment.
The mobile station identification (MSID) can be either the mobile identification number. (MIN) or the international mobile station identity (IMSI). Mobile Identification Number (MIN) is a 34 bit number that is a digital representation of the 10 digit number assigned to a mobile station. International Mobile Station Identity (IMSI) is a number up to 15 digits in length which uniquely identifies a mobile station internationally. In what follows, whenever we refer to a mobile identification number, it is implicit that an IMSI could very well be used in the place of MIN.
This results in the mobile station getting connected to an initial service unit via a voice connection. A Temporary Reference Number (TRN) identifying the mobile switching center and the mobile station is allocated for the mobile station at the mobile switching center. The TRN can be a mobile station identification (MSID), a telephone directory number or any other number.
If the TRN is not an MSID, a unique and temporary mobile identification (MSID) must also be allocated for use during the service programming procedure.
The TRN and, if possible, the temporary mobile station identification (MSID) if one is allocated, the MSID presently in the mobile station, and the electronic serial number are sent to the service unit during voice connection set up. It may not be possible to send MSIDs and the electronic serial number to the service unit since some systems on the voice connection set up path may allow only valid directory numbers or allow only directory numbers assigned to the MSC to be passed.
If it is determined that the initial service unit is not the desired service unit, the voice call gets forwarded to one service unit after another until a desired service unit is reached. The TRN, and possibly the MSID and the electronic serial number, also get sent to the final service unit.
The final service unit selects a home location register within the communications network with which the mobile station is to be associated.
The home location register then gets associated with the mobile switching center by the home location register sending a message containing the TRN to the mobile switching center. The home location register is able to send a message to the mobile switching center because the TRN identifies the mobile switching center. The mobile switching center uses the TRN to identify the mobile station whose over-the-air service programming is being carried on. The mobile switching center sends a message back to the home location register containing the temporary MSID, if one was allocated at the mobile switching center, the MSID presently contained in the mobile station, and the mobile station""s electronic serial number, if these were not received at the final service unit during voice call set-up. If the TRN is distinct from the temporary mobile identification number, it is released at the mobile switching center.
Hereafter, information regarding the mobile station contained at any network element is referenced using the temporary MSID, which could be the TRN itself, and the mobile station""s electronic serial number.
The service unit or the home location register may query, via the communication network, the mobile station for some information contained in the mobile station. The service unit or the home location register may allocate a new permanent MSID for the mobile station and transfer service programming information, possibly including the newly allocated permanent MSID, into the mobile station via the mobile switching center using the communications network. The service unit also transfers service programming information associated with the mobile station into the home location register.
After the service programming information is successfully transferred to the mobile station, the service unit or the home location register sends a message to the mobile station via the communications network instructing it to transfer the service programming information to its non-volatile memory. The information sent to the mobile station is also stored in non-volatile memory in the HLR and/or authentication center (AC).
The mobile switching center is used merely as a conduit for messaging performed between the home location register and the mobile station and between the service unit and the mobile station.
The home location register includes a database that contains registration and user profile information for the system subscribers. The mobile switching center provides interconnection services among wireless subscriber stations, and between wireless subscriber stations and the public switched telephone network (PSTN) via one or more base stations (BS) under its control. The PSTN is a telecommunications network commonly accessed by ordinary telephones, private branch exchange trunks and data transmission equipment that provides service to the general public. The base station is a fixed station used for communicating with mobile stations. Depending on the context, the term base station may refer to a cell, a sector within a cell, an MSC, or other part of the cellular system.
The method of OTA service programming according to the present invention minimizes the involvement of the MSC and Visitor Location Register (VLR) with OTA processing. The VLR links to one or more MSCs, and includes a database for temporarily storing part of subscription data and, in certain cases, security related data for a mobile station currently served by its corresponding MSC.
The over-the-air service programming process also needs the involvement of the authentication center for the purpose of storing the mobile station""s security related data and for performing security related procedures needed for downloading the Authentication-Key (A-Key) to the mobile station and for invoking voice privacy and/or signaling message encryption for security purposes on the air-link between the mobile station and the base station.
The Authentication Center (AC) is an entity that manages the security aspects related to the mobile station. The Authentication-Key is a concealed bit pattern stored in the mobile station and the AC. It is used to generate and update the mobile station""s SSD, which is used for authentication, voice privacy and signaling message encryption. Shared Secret Data (SSD) is a bit pattern stored in the mobile station and known by the AC, and possibly by the VLR. Shared Secret Data is maintained during power off.
The service unit interfaces normally with the HLR. Hence communication between the service unit and the AC is generally via the HLR. To accomplish communication between the HLR and the AC, the present invention proposes new messages between the home location register and the authentication center.
Advantageous aspects of OTA service programming according to the present invention include:
1) OTA service programming according to the present invention need not involve the MSC/VLR with the details of service programming as the process is primarily one of initializing the mobile station""s and HLR""s/Authentication Center""s (AC""s) databases.
2) By minimizing the MSC/VLR involvement, enhancements to the OTA service programming process can be made without changing MSC and VLR software.
3) The HLR/AC controls the service programming process acting as a Service Control Point (SCP) to control over-the-air service programming.
4) For control, the CSC only needs to interface to the HLR. The voice connection to the CSC may be through the network or direct from the MSC. The method of OTA service programming according to the present invention supports either method.
5) The HLR can be chosen after the activation process begins. This allows the mobile station to activate anywhere within the operator""s service area. Given the appropriate agreements and network support, there is nothing to prevent a mobile station from being activated in any HLR having connectivity with the MSC.
6) The MSC is used merely as a conduit for messaging performed between the HLR and the mobile station.